Abrasive with press-on/flip-off center hole feature. Exclusive grit and backing are designed for jewelry applications and provide an exceptionally long life. Aluminum oxide grit, mounted on thin backing, provides outstanding results in sanding and smoothing operations. The flexible backing allows accessibility to hard-to-reach areas. Set contains 25 fine, 25 coarse, and 50 medium, 7/8" sanding discs, plus one mandrel, in a compartmented plastic box.